import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int a=0,b=0,c=0;
        while(in.hasNextInt()){
            a = in.nextInt();
            b = in.nextInt();
            c = in.nextInt();
            if(a>0 && a<1000 && b>0 && b<1000 && c>0 && c<1000){
                if(a+b>c && a+c>b && b+c>a){
                    if(a == b && b==c)
                        System.out.println("Equilateral triangle!");
                    else if((a==b  || a==c || b==c) && (a!=c || b!=c || a!=b))
                        System.out.println("Isosceles triangle!");
                    else
                        System.out.println("Ordinary triangle!"); }   
            else
                System.out.println("Not a triangle!");
            }
        }  
    }
}